enum TokenType {Rpal_Operator, Rpal_Integer, Rpal_Identirfier, 
                Rpal_Punctuation, Rpal_String, Rpal_EndOfFile, Rpal_Keyword }

public class Token {
    public Token(TokenType type, String value) {
        this.type = type;
        this.value = value;
    }
    protected TokenType type;
    protected String value;    
}

